1. Field
The present invention relates to a humanoid robot, and, more particularly, to a humanoid robot in which a shoulder joint has an improved operational Degree Of Freedom (DOF), enabling implementation of a variety of motions.
2. Description of the Related Art
Robots are mechanical devices to automatically perform certain operations or tasks, and are utilized to substitute or assist humans in various fields.
Of a variety of robots, industrial robots have a high degree of utilization. The industrial robots enable automation and unmanning of production lines, achieving an improvement in productivity. Further, industrial robots are used to implement dangerous operations in place of humans, thereby protecting humans from industrial accidents.
Recently, humanoid robots, which have an external appearance and actions similar to humans, have been developed. In the same manner as industrial robots, the humanoid robots can be committed to various industrial locations, to execute operations which humans have difficulty with. However, the primary advantage of the humanoid robots is that they provide a variety of services while coexisting with humans in daily life, rather than for the purpose of replacing humans.
To assure smooth association and cooperation in daily life between a robot and a human, it is preferred that the robot be capable of imitating various motions and gestures of humans. Since a substantial number of motions and gestures performed by humans are performed using the arms, it can be said that realizing a robot arm motion similar to that of humans is important in order to improve emotional connection between humans and robots.
Korean Patent Registration No. 0749878 discloses a humanoid robot arm wherein a shoulder joint, an elbow joint and a wrist joint have an operational DOF of 3, 1 and 3, respectively, so as to imitate arm motions of humans to some extent.
However, in the disclosed conventional robot arm, the shoulder joint has only a rotational DOF of 3, having a limit to naturally implement various motions and gestures of humans.
Another problem of the conventional robot arm having the above-described configuration is that the robot arm is moved in a state wherein the shoulder joint is fixed to the robot body and therefore cannot achieve a wide range of movement without movement of a robot body.